1. Field of the Invention
The present invention relates to an erectable container which is composed of a single foldable plate member.
2. Description of the Prior Art
A variety of containers for containing food or the like and which are made of a board member such as paper or the like have been proposed. These containers are usually made in such a way that trapezoidal side boards are integrally provided adjacent each edge of an equilateral polygon, and adjacent edges of each side plate are made to adhere firmly to each other by adhesive tabs therebetween.
Consequently, in such a container, the shape of the upper opening is identical with, or conforms to, that of the bottom, so that the entire container is in the shape of an uninteresting truncated pyramid, making it difficult to realize novel designs.
Furthermore, when expandable material such as popcorn is put in a conventional container prior to heating, and then heated by a microwave oven and popcorn expands. If the upper opening portion is not changed so as to become generally circular, the capacity of the container does not become larger so that there is no sufficient space to continue popping the popcorn properly therein. Moreover, the conventional containers had many adhesive portions, which makes the manufacturing cost high.